NYC chowhounder having b'fast & lunch in chicago

So i need some help from my chicago chowhounders. I'm spending Saturday and Sunday in Chicago and would love some ideas for breakfast and lunch spots. Ideally your suggestions would include places we just can't find in new york, but basically i'm just looking for great local food.

My last three visitis to Potbelly have netted fake "deli meats" two x turkey, 1 x roast beef. I would advise against since a good sub sammich can be had in the big apple anyway. For local flavor, Id check out some of the pizza threads for the standard stuffed pizza recs, and maybe hit up one of the non-chain pizza joints.